1. Field of the Invention
The present invention relates to a transport stream (TS) transmission system and a transmitting apparatus, a receiving apparatus, and a TS transmission method for use in the TS transmission system and, more particularly, to a TS transmission system that transmits a TS for digital broadcast between broadcast stations.
2. Description of the Related Art
A TS transmitted from a broadcast station, which conforms to a broadcast standard, contains many null packets. Accordingly, when the TS is transmitted between broadcast stations, many null packets are exchanged, leading to a reduction in transmission efficiency.
A related technique is disclosed in Japanese Patent No. 3650018 (reference 1). The reference 1 discloses a technique allowing a video recorder to discard null packets contained in the TS at the TS recording time and insert null packets corresponding to the number of discarded packets to reproduce the TS at the reproducing time.
As described above, if many null packets are contained in the TS when the TS is transmitted between broadcast stations, transmission efficiency is reduced. However, if the null packets contained in the TS are discarded, the multiplex position of program clock reference (PCR) packets varies. This makes it impossible to reproduce a system time clock (STC) serving as reference time for synchronized reproduction of video data or audio data.